That is my understanding as well. Will be measuring these things, too. Can adjust the flow rate and amount of air injected.
One of the experiments, in progress. There have been past discussions on the use of needlewheel pumps to serve a dual purpose. Though, not a whole lot of follow-up with empirical data that I could find. Data forthcoming.
Ttystikk noted waterfalls which have been reported as one of the most efficient mechanisms. Flooming as an option as well. One benefit include not needing a separate air pump(s) and stones, among others.
Do you feel air pumps/stones are necessary or, more specifically, could be something that might be used as a point of comparison? Rate of O2 uptake higher than generally thought? Hint, hint: collecting compelling reasons to run an experiment 
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Im at least a few decades behind the latest thinking, but back when I was doing reef tanks, fluming and water falls were both considered far superior to your typical aquarium air stones for aeration. Pin wheel pumps with air injection/venturis and the whole ‘micro bubbles’ thing came along after I got out of that hobby.
I suspect that fluming and waterfalls will still be pretty much equal to any version of micro bubbles as far as reaching 100% DO, but thats just a guess on my part.
Im looking forward to more of your results!!!
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Reefers gave me the confidence to build my waterfall driven system. It has worked faultlessly ever since.
Recently, my chiller failed. Even with water temperatures hitting the mid 70s, the water is clean and roots are healthy. If anything, the plants are growing we’ve faster!
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Would you happen to have a photo of what the waterfall portion of your set-up looks like?
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Yes, there are a lot of interesting differing techniques out there.
The micro-bubble thing is interesting but the origin of the term, I believe, had to due with bubble size that is exceedingly small. Using specialized equipment. So small, in fact, the bubbles are almost not visible and stay in solution for quite awhile (which could be good if recirculating through a large volume of solution). There are some research papers floating around and some you-tube videos but the equipment to produce what they are doing is fairly pricey. I think they were claiming that they
would achieve supersaturation using this technique some how. The term has seemingly been usurped by other experimenters to mean bubbles that are something smaller than what airstones would produce by using venturi and such. In this case, we would not see supersaturation. So, the term seems a bit muddied.
Then there is the whole hydrolysis thing. Also interesting but with the downsides of decreased
reliability, reliance on power, cost, and the unclear effect of using such a set-up.
It seems that the aquarium folk probably have some of the most accurate results and overall
experience simply due to them being particularly sensitive to maintaining DO levels.
From what I can recall from memory, there was an individual on another forum that ran a set of experiments some time ago comparing the different aeration techniques. I think he came to the conclusion that the waterfall technique produced the highest level of saturation. Fluming was nearly equivalent. And, airstones were somewhere lower on the list. Still sufficient but lower. I have not seen similar tests (that were as thorough) backing his conclusions but the anecdotal consensus is that his results are accurate.
I have an optical DO probe and I’ll measure what I’m seeing here once I get this thing built out fully. Will be fun!
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I run an RDWC system. Think of an Undercurrent, only the recirculating pump is in the control bucket (‘epicenter’) and it feeds a manifold that delivers water directly to an elbow fitting in the lid of each tubsite. That water drop is the waterfall.
Water then runs via gravity back to the control bucket through lines near the bottom of each tubsite. The control bucket also has the coil for chilling the water.
I did it this way after noticing that in a standard Undercurrent system, the best oxygenated bucket was the only one they didn’t want you putting plants in!
Having a waterfall in the lid means that there is more churning and movement in the bucket for the roots. It automatically oxygenates. It breaks surface tension, preventing any surface scum from forming. The splash wets the bucket so the plant gets watered no matter what the water level is, making water level much less of a factor.
My chiller has been down for a month and my plants are healthy. Apparently this approach even eliminates the need for chilled water, which to me is an amazing benefit!
I’m going to copy this post into my own thread to explain the waterfalls to those who are reading there. You’re more than welcome to check it out, it’s here:
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Supersaturation is nice but unnecessary.
In fact, as demonstrated above, air pumps are also unnecessary. And air stones. And the lines to connect them.
These are all systems designed to correct for weakness in the fundamental design- as I hinted above, the Undercurrent system is flawed- or just something else for hydro stores to sell to the customer.
Mother Nature doesn’t need supersaturated water for the roots, why should we need it to grow plants that are anything but exotic?
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Hi man; looks like you think a lot like me: less = more. I ordered a Slucket system but suspect they e gone under since their site is dark and they aren’t responding to order questions. While I deal with that mess; going to just DIY it. Question: where is your drain located?
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@CatalystX, check out Ttystikks set-up at the following link if you have questions on how he has his system set-up: Vertical farming @Ttystikk - #142 by Ttystikk
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Each of my tubs has 4 one inch bulkhead fittings, two in each side, placed as low as possible. This was done to prevent clogs and maximise installation options.
Ok. Gotcha. So the tubs aren’t filling with water then. Now I get the top feeding and your reference to the splash effect. I don’t have the height to do a vertical grown in my space; the reason I was going with the Sluckets; so bummed that they seem to have gone under without notification or refund for already placed orders. Anyway; think I’m going to stick to the posiflow concept from the bottom up with 2 drains at the water line to avoid clogging from the roots. As you’ve mentioned; it’s all about the waterfall effect and the resulting DO; thinking of just creating a waterfall with a pump in my control bucket to maintain the high DO; figure moving the solution through the lines and then up into the buckets through lava rock will keep it adequately oxygenated; I use the lava rock as my growth medium for my bacteria.
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My tubs will definitely get as full as I want, but they are not sensitive to water level because of the splash effect from the waterfalls.
There is no need to run vertical with RDWC. I just do because of the research program I’m running.
Sorry to hear the bad news about Sluckets. It sucks that they take your money and then disappear.
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Mother Nature may not need it, or provide it, but growers of all types have been going out of their way to improve on mother nature since cultivation began way back when. I dont see anything wrong with helping mom out some - especially of it improves yields, quality, is faster, easier, cheaper, etc etc 
Mother nature doesnt do hydro, or LED, or HPS lights, or have special additives, or selective trimming, or maintain optimum temps, or do selective breeding, or keeping PH, EC, etc within optimum limits, or providing extra O2 or CO2, when possible, treating for pests, diseases, etc etc etc.
By doing everything we can to help out, we get more, better, faster results. Thats the whole point of this website - to grow better weed than mother nature does by herself. At least, thats what Im trying to do
If you dont believe in helping mother nature out, then just toss some seeds out the back door and hope for the best
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Mother Nature most certainly does do hydro. She does do selective breeding- through repeated testing to extremes. I could discuss the rest of your list at length.
Simply ‘improving’ on things blithely isn’t the way forward. Making specific improvements with a firm grasp of the underlying physics and/or biology of the situation is required to make those improvements that will generate desired results.
In the case of dissolved oxygen, achieving full saturation in the solution is very easy and going beyond it is rather difficult and doesn’t help the plants any. All it does is correct any deficiencies in the cultivation system itself, if any.
Where did you buy your system from? If it was from slucketbuckets.com, that is a reseller. It is not the OEM.
If you bought this using a CC or paypal, then you should initiate a chargeback as soon as possible if they are being unresponsive.
And, as a note, the system in this op is utilizing the buckets from slucket but the remainder of the system is DIY. You can still obtain the individual growth containers and reservoir containers individually or an entire system from Hydrofarms, for instance.
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I’m not going to say that this system (the subject of this thread) is part of a research program but I will say part of the intent is research in nature. Since you are running a research program, you can see the value of running experiments and being able to measure the effects of changing variables in such experiments.
No, we get what you are saying. You have noted that the waterfall method is the best method for oxygenating a nutrient solution. I would tend to agree that this is a very good method for oxygenating a solution but will stop short of agreeing that it’s the best.
We are veering off topic but when I hear things like “it doesn’t help” in reference to super-saturation, I can’t help but to ask to see the research. Until then, it is anecdotal and we are not moving forward. There are a few but contradictory studies on this topic, but here is one for instance:
Effect of Supersaturation of Dissolved Oxygen on the Growth of Tomato Plants and Nutrient Uptake in Hydroponic Culture. Gouki TANAKA, Youhei YAMASHITA, Kazushige NAKABAYASHI :
The concentration of dissolved oxygen in a culture solution is one of the most important environmental factors affecting the growth of the tops and roots of plants under hydroponic culture. In particular, the roots of tomatos readily absorb oxygen in the solution, and are thus sensitive to the concentration of dissolved oxygen. Thus, the effects of dissolved oxygen concentration on the morphology and growth of roots, water uptake rate and nutrient uptake were investigated. In hydroponic culture, the supply of dissolved oxygen is essential. Previously, we reported that supersaturation of dissolved oxygen in culture solution promoted the uptake of phosphate. In the present study, we found that supersaturation of dissolved oxygen in culture solution low in nitrogen and phosphate led to an increase in plant height, fresh weight of stems and leaves and root weight. It also increased the phosphorus concentration in the sap, stems, leaves and fruits of tomato plants.
I would welcome a discussion on this and can start a separate thread if we want to argue our viewpoints on DO further.
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@CatalystX. Going off topic. Please move the discussion regarding Ttystikk’s system to a different thread. Thanks.
Was from a reseller; finally heard back from the guy; think he’s maybe not the best communicator but is an honest soul. My system will be shipping out next week; there was some sort of delay at the OEM.
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Phew, glad to hear that it got resolved…
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